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%I #21 May 22 2022 09:49:40
%S 2,3,13,29,31,37,41,53,59,67,71,79,89,97,103,107,109,113,127,151,167,
%T 173,179,181,193,211,223,227,241,257,269,281,293,307,317,331,337,373,
%U 379,383,401,409,421,431,433,439,449,487,509,521,523,547,563,569,599
%N Primes that are not squares mod 19.
%C Inert rational primes in the field Q(sqrt(-19)). - _N. J. A. Sloane_, Dec 25 2017 [Corrected by _Jianing Song_, Dec 24 2018]
%C Primes p such that p^9 == -1 (mod 19). Primes congruent to {2, 3, 8, 10, 12, 13, 14, 15, 18} modulo 19. - _Jianing Song_, Dec 24 2018
%H Vincenzo Librandi, <a href="/A191063/b191063.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="https://oeis.org/index/Pri#primes_decomp_of">Index to sequences related to decomposition of primes in quadratic fields</a>
%t Select[Prime[Range[200]], JacobiSymbol[#,19]==-1&]
%o (Magma) [p: p in PrimesUpTo(599) | JacobiSymbol(p, 19) eq -1]; // _Vincenzo Librandi_, Sep 11 2012
%o (PARI) isok(p) = isprime(p) && !issquare(Mod(p, 19)); \\ _Michel Marcus_, Dec 25 2018
%K nonn,easy
%O 1,1
%A _T. D. Noe_, May 25 2011